<template>
  <view>
    <!-- 使用自定义的搜索组件 -->
    <my-search @click="gotoSearch"></my-search>
    <view class="scroll-view-container">
      <!-- 左侧的滑动区域 -->
      <scroll-view class="left-scroll-view" scroll-y="true" :style="{height: wh + 'px'}">
       <block v-for="(item, i) in cateList" :key="i">
         <view :class="['left-scroll-view-item', i === active ? 'active' : '']" @click="activeChanged(i)">{{item.name}}</view>
       </block>
        
      </scroll-view>
      <!-- 右侧的滑动区域 -->
      <scroll-view class="right-scroll-view" scroll-y="true" :style="{height: wh + 'px'}" :scroll-top="scrollTop">
        <view class="cate-lv2" v-for="(item2, i2) in cateLevel2" :key="i2">
          <!-- 二级分类的标题 -->
          <view class="cate-lv2-title">/  {{ item2.name }} /</view>
          <!-- 当前二级分类下的三级分类列表 -->
          <view class="cate-lv3-list">
            <!-- 三级分类的Item项 -->
            <view class="cate-lv3-item" v-for="(item3, i3) in item2.goods" :key="i3" @click="gotoGoodsList(item3)">
              <!-- 三级分类的图片 -->
              <image :src="item3.picture"></image>
              <!-- 三级分类的文本 -->
              <text>{{ item3.name }}</text>
            </view>
          </view>
        </view>     
      </scroll-view>
    </view>
  </view>
</template>

<script>
  import badgeMix from '@/mixins/tabbar-badge.js'
  export default {
    mixins: [badgeMix],
    data() {
      return {
        //当前设备可用高度
        wh: 0,
        cateList: [],
        active: 0,
        //二级分类列表
        cateLevel2: [],
        scrollTop: 0
      };
    },
    onLoad() {
      const sysInfo = uni.getSystemInfoSync()
      this.wh = sysInfo.windowHeight - 50
      
      this.getCateList()
    },
    methods:{
          //获取分类列表的数据
          async getCateList() {
            try {
              const {data: res} = await uni.$http.get('/home/category')
              this.cateList = res.result;
              
              //为二级分类赋值
            this.cateLevel2 = res.result[0].children;
            } catch (error) {
              uni.$showMsg();
              console.error(error);
            }
            
            
          },
          // 切换激活状态
          activeChanged(i) {
            this.active = i;
            
            //重新为二级分类赋值
            this.cateLevel2 = this.cateList[i].children;
            
            this.scrollTop = this.scrollTop === 0 ? 1 : 0;
          },
          //跳转到商品列表页面
          gotoGoodsList(item) {
            uni.navigateTo({
              url: '/subpkg/goods_detail/goods_detail?goods_id=' + item.id
            })
          },
          gotoSearch() {
            uni.navigateTo({
              url: '/subpkg/search/search'
            })
          }
        }
      }
</script>

<style lang="scss">
.scroll-view-container {
  display: flex;
  .right-scroll-view {
    background-color: #FFFFFF;
  }
  .left-scroll-view {
    width: 120px;
    
    .left-scroll-view-item {
      background-color: #f7f7f7;
      line-height: 60px;
      text-align: center;
      font-size: 12px;
      
      &.active {
        background-color: #FFFFFF;
        position: relative;
        
        &::before {
          content: ' ';
          display: block;
          width: 3px;
          height: 30px;
          background-color: #CFB267;
          position: absolute;
          top: 50%;
          left: 0;
          transform: translateY(-50%);
        }
      }
    }
  }
}

.cate-lv2-title {
  font-size: 12px;
  font-weight: bold;
  text-align: center;
  padding: 15px 0;
}

.cate-lv3-list {
  display: flex;
  flex-wrap: wrap;
  
  .cate-lv3-item {
    width: 33.33%;
    display: flex;
    flex-direction: column;
    justify-content: center;
    align-items: center;
    margin-bottom: 10px;
    
    image {
      width: 80px;
      height: 80px;
    }
    
    text {
      font-size: 12px;
    }
  }
}
</style>
